Reclosing circuit-interrupting device



y 1944. s. R. SMITH, JR

RECLOSING CIRCUIT-INTERRUPTING DEVICE Filed April 16, 1942 J t m. w i a v m a a 4 m 7 H M .J M W M y l.l l a;

Patented May 2, 1944 RECLOSING CIRCUIT-INTERRUPTIN G DEVICE Sidney R. Smith, Jr., Pittsfield, Masa, assignor to General Electric Company, a corporation of New York Application April 16, 1942, Serial No. 439,162

8 Claims.

My invention relates to a reclosing circuitinterrupting device and more particularly to a circuit-interrupting device comprising a pinrality of fuses only one of which is connected in the associated circuit at a time.

Fuse cutouts of the reclosing type in which a second fuse link is connected into the circuit a predetermined time after the first fuse link has blown are known and have been used to some extent. However, in connection with such devices, several difiiculties havebeen encountered, among them being the replacement of the first fuse link after blowing thereof without momentary interruption of the circuit and consequent arcing. Another difficulty is in connection with providing a simple time-delay mechanism for providing the desired time delay between the blowing of one fuse and the inserting of another in the circuit, which is relatively simple and inexpensive and which is efficient and accurate in operation.

Accordingly, it is an object of my invention to provide a new and improved reclosing circuitinterrupting device which overcomes the difilculties enumerated above.

It is another object of my invention to provide a new and improved time-delay mechanism for a reclosing circuit-interrupting device.

Still another object of my invention is to pro- .vide a new and improved means for replacing the blown fuse link in a reclosing cutout without interrupting the circuit through the second fuse link until after the .circuit has been completed through the replaced blown fuse link.

Further objects and advantages of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of my invention, reference may be had to the accompanying drawing, in which Fig. 1 is a side elevation of a reclosing circuit-interrupting device embodying my invention with the cover of the time-delay device removed more clearly to illustrate the invention; Fig. 2 is a sectional view taken on line 2-2 of Fig. 1, and Fig. 3 is a front view of the lower portion of the device.

Referring now to the drawing, I have illustrated an insulator or insulating supporting member III which may be suitably supported from a pole or crossarm, not shown, as bya supporting strap or hanger generally indicated sion line or the like.

a central portion l2 of reduced diameter of insulator In. A pair of spaced line terminals I3 and II are fixedly mounted on insulator II) in any suitable manner and are provided with means, indicated at 15 and I6, respectively, for making electrical connections with a transmis- Electrically connected to upper line terminal l3 and supported from insulator III is a rigid conducting arm II projecting outwardly from terminal l3. Supported at the extreme outer end of conducting arm I! is a double contact clip or jaw member l8 having rearwardly extending spring-biased jaw portions I9 which provide gripping means or fuse link receiving means for fuse links hereinafter described. It should be understood that, where the reclosing circuit-interrupting device uses only two fuses or, in other words, is capable of reclosing the circuit once, a single conducting arm' I! may be provided and two fuse links inserted in fuse-link contact clip or jaw member I8. It should also be understood, however, that a separate supporting arm ll might be provided for each fuse link. Although I have disclosed conducting member H as preferably comprising a relatively rigid arm, this might also comat It which is adapted substantially to surround 5 prise a somewhat resilient arm.

Lower line terminal It may be supported from insulator Ill in any suitable manner as by cementing or the like or, as illustrated in Fig. l, by a strap 20 surrounding a reduced portion 2| at the lower end of insulator l0. Strap 20, preferably constructed of conducting material, is electrically connected to a rigid conductin arm 22 connected to a U-shaped member 22' fixedly attached to a rotatable shaft 23 to permit pivotal movement of arm 22. Arm 22 is biased in a clockwise direction as viewed in Fig. 1 by spring means 24. Supported at the extreme outer end of lower conducting arm 22 is a contact clip or jaw member 25 substantially identical with jaw member I8 and comprises rearwardly extending spring-biased jaw portions 26, which provide fuse link receiving means for gripping a fuse link to be described hereinafter.

A first fuse link, generally indicated at 21 comprises a pair of flexible cables 28 spaced apart at their inner ends which are interconnected by a fusible element, not shown, enclosed within a tube 29, preferably formed of horn fiber or other material that is characterized by the ability to give off ages in the presence of the heat of an electric are, which gas tends to extinguish said electric arc. At the outer ends of the cables 28 of fuse link 21 are provided fuse link terminals comprising loops 33 and stop members 3|. The loops 33 are provided so that the fuse link 21 may readily be handled by means of a switch stick. The lower cable portion 23 of fuse link 21 is first inserted into one of the gripping portions 26 of jaw member 25 and thereafter, by means of a switch stick inserted in the upper fuse link loop 30, lower conducting arm 22 is rotated against the force of spring means 24 until upper stop member 3i is above Jaw portion IQ of upper contact clip or jaw member I 8. The upper cable portion 23 is then inserted so that one of the spring-biased jaw portions l9 firmly grips it and stop member 3| prevents it from slipping through Jaw portions IS. The fuse link 21 is thus held under tension and is connected in the circuit between spaced line terminals l3 and I4. It should be understood that the expression "first fuse link used in this specification and the claims hereinafter refers to any fuse link inserted between conducting arms [1 and 22 whether it be the fuse link originally provided or a subsequent replacement fuse link.

In order that a second fuse link may be connected into the circuit upon blowing of first fuse link 21, insulator i is provided with a third terminal 32 which is adjacent to terminal [4 but spaced sufllciently therefrom for satisfactory insulating purposes under all voltage conditions normally encountered. Pivotally connected to third terminal 32 is a conducting arm 33 having at the extreme outer end thereof a contact clip or jaw member 34 identical with jaw members l3 and 25 comprising rearwardly extending spring-biased jaw portions or gripping members 35 which provide gripping portions for receiving a fuse link therebetween. Conducting arm 33 is provided with suitable spring-biasing means, not shown, causing member 33 to rotate in a clockwise direction as viewed in Fig. 1, thereby providing tension on a second fuse link generally indicated at 35 inserted between the Jaw portions provided on conducting arms l1 and 33. Second fuse link 36 is identical with first fuse link 21 and the corresponding parts thereof are designated by the same reference numerals as are the corresponding parts of first fuse link 21. Since the third terminal 32 is normally insulated from line terminal I4, fuse link 36, is not connected between line terminals I3 and I4 when fuse link 21 is in the unblown condition. Although the upper terminals of fuse links 21 and 38 are both connected between the gripping portions of contact clip or jaw member l8, it should be understood that a second conducting arm similar to l1 might be provided for fuse link 35 as was mentioned above.

In order to connect second fuse link 38 into the circuit between line terminals I3 and I4 upon blowing of fuse link 21, rigid conducting arm 22 under the force of spring means 24 is adapted to rotate with shaft 23 rapidly separating the remaining portions of fuse link 21 and, consequently, rapidly extinguishing the are formed. At the extreme downward movement of conducting arm 22, it is adapted to be electrically connected with a switching member 31 pivotally supported at 33 by third terminal 32. A suitable stop member 33 is provided on third terminal 32 to limit the clockwise rotation of switching member 31. The extreme outer end of switching member 31 is provided with contact prongs or diverging portions 43 between which conducting arm 22 moves under the force of spring means 24 upon rupture of first fuse link 21 and the electrical circuit between arm 22 and switching member 31 is completed. The electrical circuit from lower line terminal 14 to the lower terminal of fuse link 38 is completed through conducting strap 20, conducting arm 22, pivotally mounted switching member 31, third terminal 32, and conducting arm 33.

By means of the pivotally mounted switching member 31, it is possible to replace the first fuse link 21 upon blowing thereof without any momentary arcing of the contracts or interruption of the circuit through second fuse link 36 since, during the refusing operation, pivotally mounted switching member 31 follows conducting arm 22 and remains in electrical contact therewith after first fuse link 21 has been inserted as indicated by the dotted position shown in Fig. 1. After first fuse link 21 has been replaced, pivotally mounted switching arm 31 is moved back to the full-line position indicated in Fig. 1 by inserting a. switch stick into ring 4| attached to switching member 31 as by clamp 42 and pulling downward on ring 4i. Thus, the circuit through second fuse link 36 is not broken until the first fuse link 21 has been replaced and consequently no arcing occurs.

Since spring means 24 moves conducting arm 22 at high speed, it might be possible to reclose the circuit through second fuse link 36 before a temporary fault is cleared by first fuse link 21 and, accordingly, time-delay means are usually provided so that the circuit between line terminals I3 and i4 is reclosedonly after a predetermined time has elapsed. However, in order to provide satisfactory operation, it is desirable that conducting arm 22 upon blowing of first fuse link 21 initially moves at high speed without any time delay to insure high-speed separation of the terminals of first fuse link 21. Also prior to electrical engagement between switching member 31 and arm 22, it is desirable that arm 22 again move at high speed to insure firm engagement between these two conducting members. To this end I provide the time-delay mechanism generally indicated at 43 which provides a simple and compact means by which conducting arm 22 is caused to move first at high speed, then is retarded sufiiciently to give the desired time delay, and, subsequently, is again permitted to move at high speed. The time-delay mechanism generally indicated at 43 comprises a casing 44 within which is mounted an escapement mechanism comprising pendulum 45 pivotally mounted at 46 and a gear 41 provided with teeth 43 over a substantial portion of the circumference thereof but provided also with a toothless portion 49. The escapement pendulum 45 is adapted to engage with the teeth 48 of gear 41. The shaft 23 to which conducting arm 22 is fastened extends through casing 44 and is rotatable therein. Mounted upon the shaft 23 within the casing 44 is a gear 50 meshed with a pinion 5i fixedly mounted to gear 41. Upon blowing of fuse link 21, conducting arm 22 begins to rotate in a clockwise direction in'response to the force of spring means 24 and, by virtue of the toothless portion 49 of gear 41, arm 22 may move at high the toothless portion 49 of gear 41 again comes into play and arm 22 is permitted to move at high speed without being further impeded in its final downward motion firmly to engage switching member 31 and complete the circuit through second fuse link 36.

The operation of the reclosing circuit-interrupting device described above will be obvious in view of the detailed description included above and no further description will be included here.

As a result of the improvements hereinbefore described, a reclosing circuit-interrupting device is provided whereby refusing of the device may be accomplished without momentary arcing or momentary interruption of the circuit and a simple and efficient time-delay device is provided constructed so that high-speed separation of the parts of the blown fuse to insure circuit interruption is provided together with assurance that the circuit will be satisfactorily closed through the second fuse link after a predetermined time delay.

Although a preferred embodiment of the invention has been disclosed in complete detail so as to insure a complete understanding of the invention, it is contemplated that details of the disclosed structure are capable of modifications and that other applications and features of the invention may occur to those skilled in the art. Hence, it is intended in the appended claims to cover all such modifications and changes as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States:

1. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms projecting outwardly from said supporting member each terminating in a fuselink receiving means, each of said arms being connected to one of said line terminals, 2. first fuse link carried between said fuse-link receiving means, a third terminal adjacent to but spaced from one of saidline terminals, 9, second fuse link electrically interconnecting said third terminal and one of said lineterminals, a pivotally mounted switching member electrically connected to said third terminal, and means for causing the projecting arm connected to said one line terminal adjacent said third terminal to engage conductively with said pivotally mounted switching member upon blowing of said first fuse link to connect electrically said second fuse link between said line terminals, said pivotally mounted switching member being arranged so that replacement of said first fuse link without interrupting the circuit through said second fuse link until the current path through said first fuse link has been reestablished may be accomplished.

2. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnecting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, a pivotally mounted current transfer member, movable means for electrically engaging said current transfer member for causing said second fuse link to be connected in the circuit between said line terminals after blowing of said first fuse link, said pivotally mounted current transfer means to permit replacement of said first fuse link without interrupting the circuit through said second fuse link and means for electrically'separating said current transfer means from said movable member when the current path through said first fuse link has been reestablished.

3. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnecting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link, current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of said first fuse link, and time-delay means for causing said current transfer means to move first at high speed, then at lowspeed to give the desired time delay and, subsequently, at high speed satisfactorily to complete the circuit through said second fuse link.

4. In a reclosing circuit-interrupting device,

- the combination of an insulating supporting member, a pair of spaced line terminals mount- I link adapted to be connected between said line terminals upon blowing of said first fuse link current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of said first fuse link, and time-delay means including an escapement mechanism for causing said current transfer means to move first at high speed, then at low speed to give the desired time delay, and, subsequently, at high speed satisfactorily to complete the circuit through said second fuse link.

5. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals mounted on said member, a first fuse link electrically interconnecting said line terminals, a second fuse link adapted to be connected between said line terminals upon blowing of said first fuse link current transfer means for connecting said second fuse link in the circuit between said line terminals a predetermined time after the blowing of member being arranged to follow said movable 15 said first fuse link, and time-delay means including an escapement mechanism comprising an escapement gear having a toothless portion for causing said current transfer means to move first at high speed, then at low speed to give the desired time delay, and, subsequently, at high speed satisfactorily to. complete the circuit through said second'fuse link.

6. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms biased for relative separation projecting outwardly from said supporting member each terminating in a fuse link receiving means, each of said arms being electrically connected to one of said line terminals, a first fuse link carried between said fuse link receiving means, a third terminal adjacent to but spaced from one of said line terminals, a second fuse link electrically interconnecting said third terminal and the other of said line terminals, means including the projecting arm connected to said one line terminal adjacent said third terminal for connecting said second fuse link into the circuit between said line terminals .plete the circuit through said second fuse link.

7. In a reclosing circuit-interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms biased for relative separation projecting outwardly from said supporting member each terminating in a fuse link receiving means, each of said arms being electrically connected to one of said line terminals, a first fuse link carried between said fuse link receiving means, a third terminal adjacent to but spaced from one of said line terminals, a second fuse link electrically interconnecting said third terminal and the other of said line terminals, means including the projecting arm connected to said one line terminal adjacent said third terminal for connecting said second fuse link into the circuit between said line terminals upon blowing of said first fuse link, and time-delay means including an escapement mechanism for causing said projecting arm connected to said one line terminal adjacent said third terminal to move first at high speed, then at low speed to give the desired time delay, and, subsequently, at high speed satisfactorily to complete the circuit through said second fuse link.

8. In a reclosing circuit interrupting device, the combination of an insulating supporting member, a pair of spaced line terminals fixedly mounted on said supporting member, a pair of conducting arms projecting outwardly from said supporting member each terminating in a fuse link receiving means, each of said arms being connected to one of said line terminals, a first fuse link carried between said fuse link receiving means, a third terminal adjacent to but spaced from one of said line terminals, a second fuse link electrically interconnecting said third terminal and one of said line terminals, a pivotally mounted. switching member electrically connected to said third terminal, means for causing the projecting arm connected to said one line terminal adjacent said third terminal to engage oonductively with said pivotally mounted switching member upon blowing of said fuse link to connect electrically said second fuse link between said line terminals, said pivotally mounted switching member being arranged to follow saidprojecting arm when replacing said first fuse link, and means for electrically separating said switching member from said projecting arm whereby replacement of said first fuse link without interrupting the circuit through said second fuse link until the current path through said first fuse link has been reestablished may be accomplished.

SIDNEY R. SMITH, JR. 

